DOI QR코드

DOI QR Code

Effects of Building-Roof Cooling on Flow and Air Temperature in Urban Street Canyons

  • Kim, Jae-Jin (Department of Environmental Atmospheric Sciences, Pukyong National University) ;
  • Pardyjak, Eric (Department of Mechanical Engineering, University of Utah) ;
  • Kim, Do-Yong (Department of Environmental Engineering, Mokpo National University) ;
  • Han, Kyoung-Soo (Department of Spatial Information Engineering, Pukyong National University) ;
  • Kwon, Byung-Hyuk (Department of Environmental Atmospheric Sciences, Pukyong National University)
  • Received : 2013.07.15
  • Accepted : 2013.12.06
  • Published : 2014.05.31

Abstract

The effects of building-roof cooling on flow and air temperature in 3D urban street canyons are numerically investigated using a computational fluid dynamics (CFD) model. The aspect ratios of the building and street canyon considered are unity. For investigating the building-roof cooling effects, the building-roof temperatures are systematically changed. The traditional flow pattern including a portal vortex appears in the spanwise canyon. Compared with the case of the control run, there are minimal differences in flow pattern in the cases in which maximum building-roof cooling is considered. However, as the building roof becomes cooler, the mean kinetic energy increases and the air temperature decreases in the spanwise canyon. Building-roof cooling suppresses the upward and inward motions above the building roof, resultantly increasing the horizontal velocity near the roof level. The increase in wind velocity above the roof level intensifies the secondarily driven vortex circulation as well as the inward (outward) motion into (out of) the spanwise canyon. Finally, building-roof cooling reduces the air temperature in the spanwise canyon, supplying much relatively cool air from the streamwise canyon into the spanwise canyon.

Keywords

References

  1. Akbari, H., H. D. Matthews, and D. Seto, 2012: The long-term effect of increasing the albedo of urban areas. Environ. Res. Lett., 71, 1-10.
  2. Baik, J.-J., and J.-J. Kim, 1998: A numerical study of flow and pollutant dispersion characteristics in urban street canyons. J. Appl. Meteorol., 38, 1576-1589.
  3. Kim, J.-J., and J.-J. Baik, 1999: A numerical study of thermal effects on flow and pollutant dispersion in urban street canyons. J. Appl. Meteorol., 38, 1249-1261. https://doi.org/10.1175/1520-0450(1999)038<1249:ANSOTE>2.0.CO;2
  4. Kim, J.-J., and J.-J. Baik, 2001: Urban street-canyon flows with bottom heating. Atmos. Environ., 35, 3395-3404. https://doi.org/10.1016/S1352-2310(01)00135-2
  5. Kim, J.-J., and J.-J. Baik, 2005: Physical experiments to investigate the effects of street bottom heating and inflow turbulence on urban street-canyon flow. Adv. Atmos. Sci., 22, 230-237. https://doi.org/10.1007/BF02918512
  6. Kim, J.-J., and J.-J. Baik, 2010: Effects of street-bottom and building-roof heating on flow in three-dimensional street canyons. Adv. Atmos. Sci., 27, 513-527. https://doi.org/10.1007/s00376-009-9095-2
  7. Kim, M., R. Park, and J.-J. Kim, 2012: Urban air quality modeling with full $O_3-NO_x-VOC$ chemistry: Implications for $O_3$ and PM air quality in a street canyon. Atmos. Environ., 47, 330-340. https://doi.org/10.1016/j.atmosenv.2011.10.059
  8. Kovar-Panskus, A., L. Moulinneuf, E. Savory, A. Abdelqari, J.-F. Sini, J.-M. Rosant, A. Robins, and N. Toy, 2002: A wind tunnel investigation of the influence of solar-induced wall-heating on the flow regime within a simulated urban street canyon. Water Air Soil Pollut. Focus, 2, 555-571. https://doi.org/10.1023/A:1021345131117
  9. Niachou, A., K. Papakonstantinou, M. Santamouris, A. Tsangrassoulis, and G. Mihalakakou, 2001: Analysis of the green roof thermal properties and investigation of its energy performance. Energ. Buildings, 33, 719-729. https://doi.org/10.1016/S0378-7788(01)00062-7
  10. Niachou, K., I. Livada, and M. Santamouris, 2005: A study of temperature and wind distribution inside two urban street canyons in Athens. International Conference on Passive and Low Energy Cooling for the Built Environment, Santorini, Greece, 125-131.
  11. Richards, K., M. Schatzmann, and B. Leitl, 2006: Wind tunnel experiments modelling the thermal effects within the vicinity of a single block building with leeward wall heating. J. Wind Eng. Ind. Aerod., 94, 621-636. https://doi.org/10.1016/j.jweia.2006.02.003
  12. Sini, J.-F., S. Anquetin, and P. G. Mestayer, 1996: Pollutant dispersion and thermal effects in urban street canyons. Atmos. Environ., 30, 2659-2677. https://doi.org/10.1016/1352-2310(95)00321-5
  13. Uehara, K., S. Murakami, S. Oikawa, and S. Wakamatsu, 2000: Wind tunnel experiments on how thermal stratification affects flow in and above urban street canyons. Atmos. Environ., 34, 1553-1562. https://doi.org/10.1016/S1352-2310(99)00410-0
  14. Xie, X., C.-H. Liu, and D. Y. C. Leung, 2007: Impact of building facades and ground heating on wind flow and pollutant transport in street canyons. Atmos. Environ., 41, 9030-9049. https://doi.org/10.1016/j.atmosenv.2007.08.027
  15. Xie, X., C.-H. Liu, D. Y. C. Leung, and M. K. H. Leung, 2006: Characteristics of air exchange in a street canyon with ground heating. Atmos. Environ., 40, 6396-6409. https://doi.org/10.1016/j.atmosenv.2006.05.050
  16. Yoon, Y.-H., B.-J. Park, and W.-T. Kim, 2006: Current states of rooftop greening in Japan. J. Korean Soc. People Plants Environ., 9, 27-32. (in Korean with English abstract)

Cited by

  1. 도시 협곡에서 건물 지붕 냉각이 스칼라 물질 확산에 미치는 영향 vol.24, pp.3, 2014, https://doi.org/10.14191/atmos.2014.24.3.331
  2. GIS 자료사용을 위한 건물 구축 알고리즘 개선 및 건물 주변 흐름과 확산 분석 vol.30, pp.6, 2014, https://doi.org/10.7780/kjrs.2014.30.6.4
  3. 벡터 형식의 GIS 자료와 CFD 모델을 이용한 도시 지역 상세 대기 흐름 연구 vol.30, pp.6, 2014, https://doi.org/10.7780/kjrs.2014.30.6.6
  4. GIS 자료를 활용한 대도시 지역 기상관측소 관측환경 평가 vol.31, pp.2, 2014, https://doi.org/10.7780/kjrs.2015.31.2.13
  5. GIS 자료를 활용한 지상 바람 관측환경 분석 vol.31, pp.2, 2015, https://doi.org/10.7780/kjrs.2015.31.2.2
  6. CFD 모델을 이용한 건물군 주변의 흐름 특성 연구 vol.25, pp.3, 2014, https://doi.org/10.14191/atmos.2015.25.3.501
  7. 인공적 지형변화가 국지풍에 미치는 영향 vol.32, pp.2, 2016, https://doi.org/10.7780/kjrs.2016.32.2.10
  8. 토지 피복별 차등 가열이 도시 지역의 흐름과 기온에 미치는 영향 vol.32, pp.6, 2016, https://doi.org/10.7780/kjrs.2016.32.6.5
  9. Impacts of Traffic Tidal Flow on Pollutant Dispersion in a Non-Uniform Urban Street Canyon vol.9, pp.3, 2014, https://doi.org/10.3390/atmos9030082
  10. High-Resolution Flow Simulations Around a Steep Mountainous Island in Korea Using a CFD Model with One-way Nested Grid System vol.36, pp.4, 2014, https://doi.org/10.7780/kjrs.2020.36.4.6
  11. WRF-Chem 모델과 결합된 CFD 모델을 활용한 도시 지역의 일산화탄소 확산 연구 vol.36, pp.5, 2014, https://doi.org/10.7780/kjrs.2020.36.5.1.3
  12. 다중규모 모델을 이용한 도시 지역 흐름과 초미세먼지(PM2.5) 분포 특성 연구: Part I - 상세 흐름 분석 vol.36, pp.6, 2020, https://doi.org/10.7780/kjrs.2020.36.6.3.2